libgui: add BQ consumer buffer free notifications
This change adds a new callback for BufferQueue consumers to be notified
when the BufferQueue frees some or all of its buffers. This is needed
to retain SurfaceTexture behavior where all buffers would be freed when
the producer disconnects. This change also modifies the
SurfaceTextureGLToGLTest.EglDestroySurfaceUnrefsBuffers test to catch
when the buffers are not freed.
The implementation is a little complicated because it needs to avoid
circular sp<> references across what will be a binder interface (so wp<>
can't be used directly). It also needs to avoid the possibility of
locking the BufferQueue and consumer (e.g. SurfaceTexture) mutexes in
the wrong order.
This change also includes a few additional fixes and test cleanups.
Change-Id: I27b77d0af15cb4b135f4b63573f634f5f0da2182
diff --git a/include/gui/SurfaceTexture.h b/include/gui/SurfaceTexture.h
index 2ab2ab7..f8dc3ac 100644
--- a/include/gui/SurfaceTexture.h
+++ b/include/gui/SurfaceTexture.h
@@ -39,12 +39,20 @@
class String8;
-class SurfaceTexture : public virtual RefBase {
+class SurfaceTexture : public virtual RefBase,
+ protected BufferQueue::ConsumerListener {
public:
- // This typedef allows external code to continue referencing
- // SurfaceTexture::FrameAvailableListener during refactoring
- typedef BufferQueue::FrameAvailableListener FrameAvailableListener;
-
+ struct FrameAvailableListener : public virtual RefBase {
+ // onFrameAvailable() is called each time an additional frame becomes
+ // available for consumption. This means that frames that are queued
+ // while in asynchronous mode only trigger the callback if no previous
+ // frames are pending. Frames queued while in synchronous mode always
+ // trigger the callback.
+ //
+ // This is called without any lock held and can be called concurrently
+ // by multiple threads.
+ virtual void onFrameAvailable() = 0;
+ };
// SurfaceTexture constructs a new SurfaceTexture object. tex indicates the
// name of the OpenGL ES texture to which images are to be streamed. This
@@ -175,6 +183,12 @@
protected:
+ // Implementation of the BufferQueue::ConsumerListener interface. These
+ // calls are used to notify the SurfaceTexture of asynchronous events in the
+ // BufferQueue.
+ virtual void onFrameAvailable();
+ virtual void onBuffersReleased();
+
static bool isExternalFormat(uint32_t format);
private:
@@ -183,6 +197,13 @@
EGLImageKHR createImage(EGLDisplay dpy,
const sp<GraphicBuffer>& graphicBuffer);
+ // freeBufferLocked frees up the given buffer slot. If the slot has been
+ // initialized this will release the reference to the GraphicBuffer in that
+ // slot and destroy the EGLImage in that slot. Otherwise it has no effect.
+ //
+ // This method must be called with mMutex locked.
+ void freeBufferLocked(int slotIndex);
+
// computeCurrentTransformMatrix computes the transform matrix for the
// current texture. It uses mCurrentTransform and the current GraphicBuffer
// to compute this matrix and stores it in mCurrentTransformMatrix.
@@ -234,8 +255,8 @@
// browser's tile cache exceeds.
const GLenum mTexTarget;
- // SurfaceTexture maintains EGL information about GraphicBuffers that corresponds
- // directly with BufferQueue's buffers
+ // EGLSlot contains the information and object references that
+ // SurfaceTexture maintains about a BufferQueue buffer slot.
struct EGLSlot {
EGLSlot()
: mEglImage(EGL_NO_IMAGE_KHR),
@@ -258,6 +279,13 @@
EGLSyncKHR mFence;
};
+ // mEGLSlots stores the buffers that have been allocated by the BufferQueue
+ // for each buffer slot. It is initialized to null pointers, and gets
+ // filled in with the result of BufferQueue::acquire when the
+ // client dequeues a buffer from a
+ // slot that has not yet been used. The buffer allocated to a slot will also
+ // be replaced if the requested buffer usage or geometry differs from that
+ // of the buffer allocated to a slot.
EGLSlot mEGLSlots[BufferQueue::NUM_BUFFER_SLOTS];
// mAbandoned indicates that the BufferQueue will no longer be used to
@@ -271,10 +299,10 @@
// It can be set by the setName method.
String8 mName;
- // mMutex is the mutex used to prevent concurrent access to the member
- // variables of SurfaceTexture objects. It must be locked whenever the
- // member variables are accessed.
- mutable Mutex mMutex;
+ // mFrameAvailableListener is the listener object that will be called when a
+ // new frame becomes available. If it is not NULL it will be called from
+ // queueBuffer.
+ sp<FrameAvailableListener> mFrameAvailableListener;
// mCurrentTexture is the buffer slot index of the buffer that is currently
// bound to the OpenGL texture. It is initialized to INVALID_BUFFER_SLOT,
@@ -288,6 +316,10 @@
// if none is supplied
sp<BufferQueue> mBufferQueue;
+ // mMutex is the mutex used to prevent concurrent access to the member
+ // variables of SurfaceTexture objects. It must be locked whenever the
+ // member variables are accessed.
+ mutable Mutex mMutex;
};
// ----------------------------------------------------------------------------